- a fungus whose spores develop within asci. The ascomycetes include most molds, mildews, and yeasts, the fungal component of most lichens, and a few large forms such as morels and truffles. Compare with basidiomycete.
- Phylum Ascomycota (formerly subdivision Ascomycotina), class Ascomycetes
mid 19th century: from modern Latin Ascomycetes (former class name), from Greek askos 'sac' + muskētes 'fungi'